KERBWAY CONTENTS Contents Page 1 Introduction Page 2 Grates and Inlets Page 3 Design Charts: Mountable Kerb 1:30 Crossfall Chart 1 Barrier Kerb 1:30 Crossfall Chart 2 Mountable Kerb 1:40 Crossfall Chart 3 Barrier Kerb 1:40 Crossfall Chart 4 Hazen Grate and Sag Captures Chart 5 Centre of Road Capture Chart 6 Field Inlet Capture Chart 7 Gold Coast City Captures Chart 8 Curve Coefficients Mountable Kerb Chart 9 Curve Coefficients Barrier Kerb Chart 10 Drawings: Extended Kerb Inlets K1 Inlet Manhole K2 Standard Inlet K3 Compact Inlet K4 Inlet Manhole Top K5 Inlet Manhole Top - Compact K6 Secondary Inlets K7 Centre of Road Inlets C1,C2 Field Inlets F1 Note: AutoCAD.dwg files, K1 to F1, may be downloaded from maxq.com.au. Kerbway is a complete stormwater drainage inlet and manhole system which maintains an intact kerb line in contrast to lip-in-line systems such as Drainway and Stormway. It is based on the Manning grate fully compliant to Class D AS 3996, widely used for over 30 years and well known for being very bicycle friendly and pedestrian friendly to AS 3996 Clause 3.3.5. The 800x500 grate easily complies with AS 2856 and AS 3996 requirements for person entry and the standard 800x700 gully pit permits connection of the normal maximum allowable gully to gully pipe size of 525mm. Maintenance of an intact kerb line ensures guidance of straying vehicles back into the carriageway and the best protection for pedestrians from straying vehicles mounting the kerb at the setback required for lip-in-line construction. It also removes the risk for pedestrians proceeding along the kerb line, of walking into the setback, which has been the subject of numerous damages claims. In addition Manning grates may be used in conjunction with the look alike Hazen 600x300 grate for aesthetically pleasing results and with the Telford field inlet grate which fits the same frame as the Manning but has increased apertures for improved passage of debris. Page 1
KERBWAY STORMWATER INLET SYSTEM Introduction Kerbway is a widely used stormwater inlet system based on 800x500 grates using a standard 800x700 gully pit or a rectangular inlet man-hole. Kerbway safety advantages include: 1. Child safe 90mm kerb inlet openings. 2. Very bicycle and pedestrian friendly Manning grate. 3. Vehicle and bike safe kerb-in-line construction. 4. No pedestrian safety risk from setback into the footpath. 5. Work & traffic safety option of inlet-manhole construction. Other Kerbway design advantages include: 1. No kerb transitions with upright kerb, leading to inlet length reduction of up to 2.5m. 2. Five inlet sizes from 1000mm to 4800mm lintel length. 3. Shortest extended kerb inlet 1600mm lintel. 4. Standard inlet 1000mm overall length. 5. High efficiency capture with bars aligned to the flow. 6. Equivalent capture to most 900x600 grate inlets using up to 140mm kerb opening. All kerbside inlets have been flow tested using a 90mm kerb opening for child safe inlets to Qudm-2007. The calibration flow range is 330L/s at full scale with curves extrapolated to 500L/s by the test authority. The design is designated Kerbway to distinguish it from lip-in-line Drainway and Stormway inlets. All the inlet capacity charts in this package are based on model testing that incorporates the features listed above. Hydraulic Modelling Hydraulic modelling was carried out, at full scale, at the Urban Water Resources Centre, University of South Australia. Modelling on grade was carried out at 2.5% and 3.3% pavement crossfall with both barrier and mountable kerb. Sag inlet tests were conducted with the grate covered. Measured sag captures therefore exclude the inflow through the grate which occurs in practice. Precast Units The five lintels and inlet top are available as precast units, at competitive prices, from a number of manufacturers. Pits and inlet-manholes are cast in situ, the most economical method of construction for these items. Inlet Descriptions Kerbway inlets may be described in terms K for Kerbway, the length of the lintel, G for an 800x700 gully pit and M for an inlet-manhole. The five inlets in terms of lintel length and the overall length including transitions are: Lintel mm K1000 K1600 K2400 K3600 K4800 Barrier Kerb mm 1000 1600 2400 3600 4800 M ntable Kerb mm 3000 3600 4400 5000 6200 Construction Details Construction drawings for Kerbway inlets are Dwg K1 for K2400 to 4800 lintels, K2 for the Inlet Manhole, K3 for the 1000 lintel, K4 for the 1600 lintel, and K5&6 for precast manhole top and K6 for Hazen inlets. Kerb transition lengths are: Mountable kerb 1000mm U/S, D/S and in sag. Barrier kerb of all types no transition. Design Charts Charts are provided for each of the five lintels described, covering mountable kerb and barrier kerbs of whatever type, cross falls 2.5% and 3.0% and grades 0.5% to 16%. The sag chart covers capture for all kerb types. Blockage Blockage factors should be applied to compensate for reduced capture in the field compared with ideal test conditions. For system design apply Qudm-2007 blockage factors to chart captures as follows: Inlet on grade with grate 0.9 Inlet in sag with grate 1.0 Chamber Water Level To meet test conditions the chamber water level, measured from the D/S channel invert, must not exceed: Road grade % Depth to design water level Sag 0.05m 0.0 to 1% 0.08m >1% to 3% 0.12m >3% 0.15m Where the design chamber water level is 300mm below the D/S channel invert the allowable inlet capture on grades over 5% may be increased by 6%. Child Safety Kerbway kerb inlet openings are limited to 90mm, a desirable maximum opening to guard against small children being washed into the inlet (Qudm-2007, Sections 7.04.2 (a) (i) and 7.05.3 and Technical Note 7.05.1). Pedestrian Safety Pedestrian friendly Manning and Hazen grates with flat surface and openings <17mm are an acceptable alternatives to covers for use in pedestrian areas (AS 3996-2006 Clause 3.3.5) and roadways in residential areas. Hydraulic Efficiency Kerbway, Manning and Hazen grates, with bars running with the flow exhibit exceptional hydraulically efficiency. Hazen Grate The Hazen grate is for secondary inlets such as at sag points on intersection turnouts and on grade or wherever small size inlets are required. Design curves are based on full scale tests. Charts Kerbway System design charts: No Location and Grate Type Cross-fall Manning Grates on Grade Chart 1 Mountable Kerb 3.3% Chart 2 Barrier Kerb 3.3% Manning Grates on Grade Chart 3 Mountable Kerb 2.5% Chart 4 Barrier Kerb 2.5% Manning Grates in Sag Chart 5 All kerb types All Centre of Road Inlets Chart 6 Manning and Maxflow Grates 2.5 & 3.3% Field Inlets Chart 7 Manning and Telford Grates NA Gold Coast City Council Inlets Chart 8 Manning Grate 2.5 & 3.3% Capture Equations S10 Barrier Kerb 2.5 & 3.3% S10 Mountable Kerb 2.5 & 3.3% Hazen design charts: No Kerb and Channel Type Cross-fall Hazen Grate Chart 5 Mountable and Barrier All Chart 5 Sag capture All Page 2
MANNING GRATE 800 x 500 - MOUNTABLE KERB CHART 9 Mountable Kerb - 1:30 Crossfall Mountable Kerb - 1:40 Crossfall No Kerb Inlet Extension No Kerb Inlet Extension Grade Curve Curve Grade Curve Curve at a b c Start Q500 at a b c Start Q500 Inlet l/s l/s Inlet l/s l/s 0.2-3% 11.48-0.107-30 23 174 0-3% 10.34-0.086-25 20 164 4% 12.33-0.106-34 23 189 4% 10.91-0.079-26 15 178 8% 10.75-0.100-26 23 164 8% 9.67-0.081-22 20 154 10-12% 9.34-0.069-20 21 154 10-12% 8.44-0.054-17 20 145 16% 8.05-0.080-14 20 126 16% 7.18-0.063-11 20 118 Small Kerb Inlet Extension Small Kerb Inlet Extension Grade Curve Curve Grade Curve Curve at a b c Start Q500 at a b c Start Q500 Inlet l/s l/s Inlet l/s l/s 0.2-10% 11.48-0.007-32 23 221 0.2-10% 10.29 0.010-26 19 209 12% 13.03-0.131-36 21 190 12% 11.74-0.109-30 18 178 16% 12.70-0.174-34 23 163 16% 11.57-0.154-28.3276 18 154 Medium Kerb Inlet Extension Medium Kerb Inlet Extension Grade Curve Curve Grade Curve Curve at a b c Start Q500 at a b c Start Q500 Inlet l/s l/s Inlet l/s l/s 0.2-4% 15.66-0.057-58 50 264 0.2-4% 13.80-0.029-46 45 248 8% 16.24-0.099-60 50 254 8% 14.29-0.065-48 45 239 10-12% 16.05-0.145-56 50 230 10-12% 14.02-0.105-44 45 217 16% 15.85-0.171-54 50 215 16% 14.43-0.150-45.1 43 203 Large Kerb Inlet Extension Large Kerb Inlet Extension Grade Curve Curve Grade Curve Curve at a b c Start Q500 at a b c Start Q500 Inlet l/s l/s Inlet l/s l/s 0.2-2% 23.96-0.228-117 90 305 0-3% 18.53-0.100-78 60 287 4% 21.21-0.186-95 80 286 4% 15.49-0.043-57 60 267 8% 18.21-0.129-73 65 269 8% 14.46-0.043-49 60 252 10-12% 16.33-0.109-60 63 251 10-12% 14.02-0.065-45 60 236 16% 14.36-0.071-48 41 238 16% 12.50-0.036-37.7 35 224 Curve coefficients Sag Size Inlet Q at Grate of Extnsn a b d=200 Type Grate m L/s Hazen 600x300 0 8 115 261 Manning 800x500 0 7 115 300 Manning 800x500 S 7 125 330 Manning 800x500 M 6 103 387 Manning 800x500 L 4 73 501 Manning 2@2.4m 0 4 73 517 SAG INLETS NOTES Mathematical curves have been fitted to the test results. For flow v capture the equation is of the form y=ax^0.5+bx+c where y = the capture and x = the approach flow. For sags the equation is y=ax^2/3 -b where y = the ponded depth as a height in mm above the nominal lip level of the channel at the centre of the grate and x = the flow. All flows are in litres/second. PLEASE NOTE IF HEIGHT IS RELATED TO INVERT LEVEL OF THE CHANNEL THEN APPROX 30mm SHOULD BE ADDED TO THE CALCULATED DEPTH.
MANNING GRATE 800 x 500 - BARRIER KERB Barrier Kerb - 1:40 Crossfall No Kerb Inlet Extension Barrier Kerb - 1:30 Crossfall No Kerb Inlet Extension CHART 10 Grade Curve Curve Grade Curve Curve at a b c Start Q500 at a b c Start Q500 Inlet l/s l/s Inlet l/s l/s 0.2-2% 10.38-0.082-25 23 166 0.2-2% 11.78-0.114-31 28 175 3% - 4% 11.74-0.092-31 20 186 3% - 4% 13.04-0.115-37 24 197 8% 12.33-0.136-34 30 174 8% 13.60-0.159-40 35 185 10% 10.84-0.112-26 20 160 10% 12.16-0.141-32 24 169 12% 9.45-0.081-21 16 150 12% 10.47-0.101-25 19 159 16% 8.03-0.070-15 10 130 16% 8.91-0.086-18 12 138 Small Kerb Inlet Extension Small Kerb Inlet Extension Grade Curve Curve Grade Curve Curve at a b c Start Q500 at a b c Start Q500 Inlet l/s l/s Inlet l/s l/s 0.2-3% 10.83-0.031-28 20 199 0.- 10% 12.13-0.003-36 25 234 4-8% 10.61 0.024-28 20 221 12% 12.07-0.077-33 25 198 10% 10.83-0.031-28 20 199 16% 11.77-0.121-31 24 172 12% 10.50-0.044-26 20 187 16% 10.50-0.094-25 20 163 Medium Kerb Inlet Extension Medium Kerb Inlet Extension Grade Curve Curve Grade Curve Curve at a b c Start Q500 at a b c Start Q500 Inlet l/s l/s Inlet l/s l/s 0.2-8% 11.47 0.045-34 45 245 0.2-8% 15.28-0.025-57 52 272 12% 11.25-0.009-30 45 217 12% 14.72-0.084-50 47 237 16% 11.53-0.079-29 43 189 16% 12.51-0.040-37 42 222 Large Kerb Inlet Extension Large Kerb Inlet Extension Grade Curve Curve Grade Curve Curve at a b c Start Q500 at a b c Start Q500 Inlet l/s l/s Inlet l/s l/s 0.2-2% 18.30-0.113-75 80 278 0.2-2% 24.26-0.218-121 90 313 4% - 8% 15.75-0.067-58 65 261 4% - 8% 20.00-0.138-88 80 290 12% 13.99-0.033-47 55 249 12% 15.59-0.055-58 59 264 16% 12.22-0.011-37 45 231 16% 12.94-0.005-42 45 245 Barrier Kerb 1:40-1:30 Crossfall No Kerb Inlet Extension HAZEN GRATE 600x300 Mountable Kerb 1:40-1:30 Crossfall No Kerb Inlet Extension Grade Curve Curve Grade Curve Curve at a b c Start Q250 at a b c Start Q250 Inlet l/s l/s Inlet l/s l/s 0.2-3% 8.50-0.140-11 27 88 0.2-3% 7.45-0.116-9 27 80 4% 7.18-0.110-7 22 79 4% 6.20-0.091-6 22 70 8% 6.05-0.085-5 18 70 8% 5.24-0.067-3 18 63 12% 5.36-0.080-4 14 61 12% 4.67-0.064-3 14 55 16% 4.34-0.057-2 10 52 16% 3.83-0.046-2 10 47